If it's 4.0.1 then you should be fine. If it's 4.0.2 or higher then you'll need to downgrade. You have to go to your computer and right click the desktop. Click new and then folder. Name it whatever you want, it's up to you. I called mine mw2 theme. There are multiple folders you'll need for a full theme but since your only worrying about icons, we only need one. I will use my folder as a reference. Create a folder inside mw2 theme and call it icons. Now find a picture you would like as your app's icon. Use a photo editing tool to make it 64 by 64. Now save this to your desktop and call it the exact name of the app. (ex. App Store.png) Spaces and capitals must be included. It should say .jpg or .gif or . something at the end. Change this to .png. Now save your image to the desktop. I'm this case yours would be called Weather.png. Click and drag this into the icons folder we made. Now open up the program you use to ssh. I use winscp. Go to stash, then themes followed by a bunch of numbers and letters, and now click and drag your entire folder containing the icons folder into this area. Now copy it when it asks to. Now open up winterboard and click the name of your theme under select themes. Now press home and that's it. Hope this helped. Good luck.